Display screen or portion thereof with a graphical user interface



The sole FIGURE is a front view of a display screen with a graphicaluser interface.

The dashed broken lines show user interface elements and form no part ofthe claimed design. The dot-dash broken lines illustrate the perimeterof a display screen and form no part of the claimed design.

CLAIM The ornamental design for a display screen or portion thereof witha graphical user interface, as shown and described.